The annual Jewish festival, held on the 14th of the month Nisan, which commemorated the saving events of the Exodus from Egypt; as an institution it may have already existed in pre‐Israelite Canaan as an agricultural festival in the first month of the year, and this was absorbed into the life and ritual of the incoming Hebrews. There seems to be a record of this combination when the Israelites, after entering Canaan, are said to have kept the Passover (Josh. 5: 10) and on the following day to have eaten the produce of the land (5: 11).
The late Pentateuchal source P puts the Passover rites back into the wilderness of Sinai (Num. 9: 3, 5) but this assertion is too late to be regarded as historically reliable. From the time of Solomon (1 Kgs. 9: 25; 2 Chron. 8: 13) the Passover ritual was established, and in the reforms of Josiah (2 Kgs. 23: 21–3) there were to be regular Passover festivals in Jerusalem. Passover lambs were either roasted (Exod. 12: 8–9) or boiled (Deut. 16: 7) and were eaten at a solemn meal in the evening at which the departure from Egypt after the Lord ‘passed over’ the Israelite males but destroyed their Egyptian contemporaries was remembered. The feast of Unleavened Bread (as in Josh. 5: 11) was maintained for a full week from the Passover. The feast was of immense significance for the Jewish sense of identity as a people; it united successive generations in a family. In the NT it has significance because of the Lord's Supper as a Passover Meal, according to the synoptists, held by Jesus with his disciples in Jerusalem. They followed the traditional ritual with the first and second cups of wine and unleavened bread, but a new significance was given to the meal by Jesus by associating it with his coming death. NT writers refer to Christ as a ‘passover lamb’ (1 Cor. 5: 7) and the acclamation by John the Baptist to Jesus as ‘Lamb of God’ (John 1: 29) is held by some commentators to indicate that this gospel, which connects the death of Jesus with the timing of the slaughter of the passover lambs in the Temple (John 19: 14), had a theology of Jesus as the True Paschal Lamb who brings about the final release of his people from the slavery of sin.